Devices of the kind specified in the preamble are well known in the art. Examples of such devices are: handheld electronic devices such as remote control devices, video game controllers and mobile telephones, keyboards for text entry or playing music, switches at the dashboard or at the doors of an automobile, etc.
If real estate is scarce for accommodating the keycaps, or if the spatial distribution of the keycaps needs to comply with aesthetic requirements, an accurate positioning of the keycaps is required so as to make full use of the room available or so as to give a precise, regular character to the spatial arrangement of the keycaps. This is especially relevant to a so-called “piano key arrangement”.
The expression “piano key arrangement” indicates a lay-out of the keycaps, wherein the keycaps form a visually regular one-dimensional array or a visually regular two-dimensional array, wherein the keycaps themselves are flat and wherein neighboring ones of the keycaps are separated by a relatively very narrow gap. The lay-out of the piano keycaps requires accurate sizing and accurate mounting of the keycaps, as any difference in the orientation or in the height between a pair of neighboring ones of the keycaps is easily noticed by the user. This difference may then hamper the pleasing aesthetics of the piano-key lay-out or may interfere with the operation of the user-interface.